The Borehole Heat exchangers of today suffer from poor thermal and hydrodynamic performance. The purpose of this thesis is to improve the performance of ground source heat pump systems and thermal energy storages by increasing the energy efficiency of the Borehole Heat exchangers. For this reason, the annular coaxial Borehole Heat exchanger (CBHE) has been analyzed. This type of heat exchanger is interesting in terms of both thermal and hydrodynamic performance. A model has been set up in the program Comsol Multiphysics in order to investigate the heat transfer characteristics along the borehole.

The thermal response of a borehole field is often described by non?dimensional response factors called gfunctions.The g?function was firstly generated as a numerical solution based on SBM (Superposition BoreholeModel). An analytical approach, the FLS (Finite Line Source), is also accepted for generating the g?function. In thiswork the potential to numerically produce g?functions is studied for circular borehole fields using the commercialsoftware COMSOL.

Increased resource efficiency in an energy system could result in large economic and environmental benefits. Tekniska verken i Linköping AB (Tekniska verken) is responsible for the district heating network in Linköping. Their vision is to create the world?s most resource efficient region. An important step towards this vision is more efficient usage of produced heat, something which could be achieved through integration of a seasonal heat storage in the energy system.

In the spring of 2014 Sweco Systems AB were commissioned to design a ventilation system for a newly built preschool in Linköping. Terms from the client was that it cost efficiency would cope with the energy demands that are placed on the building. The unit chosen was a cross-flow heat exchanger, and this work is to compare it with two other heat exchangers to see if a more energy and cost efficient could have been chosen. The heat exchangers that was chosen for the comparison was a rotating- and a counterflow heat exchanger. Simulations have been made to the different heat exchangers by the manufacturers.

Gtherm is an innovation company who has an unique air heat exchanger underdevelopment. The purpose of this thesis is to provide data of suitable motors for theheat exchanger and to find suitable motor suppliers.A motor specification was designed. It is an important basis for the search of suitablemotors. A compilation was made of nine motor suppliers and the suitable motorsfrom those. The compilation can be used by GTherm in their choice of suppliers andmotors.The compilation of the demands on the motor and analysis of suppliers indicated thatthere were no standard motors available to GTherms air heat exchanger.

In the spring of 2014 Sweco Systems AB were commissioned to design a ventilation system for a newly built preschool in Linköping. Terms from the client was that it cost efficiency would cope with the energy demands that are placed on the building. The unit chosen was a cross-flow heat exchanger, and this work is to compare it with two other heat exchangers to see if a more energy and cost efficient could have been chosen. The heat exchangers that was chosen for the comparison was a rotating- and a counterflow heat exchanger. Simulations have been made to the different heat exchangers by the manufacturers.

The district heating load is seasonally dependent, with a low load during periods of high ambient temperature. Thermal energy storage (TES) has the potential to shift heating loads from winter to summer, thus reducing cost and environmental impact of District Heat production. In this study, a concept of high temperature borehole thermal energy storage (HT-BTES) together with a pellet heating plant for temperature boost, is presented and evaluated by its technical limitations, its ability to supply heat, its function within the district heating system, as well as its environmental impact and economic viability in Gothenburg, Sweden, a city with access to high quantities of waste heat.The concept has proven potentially environmentally friendly and potentially profitable if its design is balanced to achieve a good enough supply temperature from the HT-BTES. The size of the heat storage, the distance between boreholes and low borehole thermal resistance are key parameters to achieve high temperature. Profitability increases if a location with lower temperature demand, as well as risk of future shortage of supply, can be met.

The dishwasher is a wide spread product that occurs in many households. It saves the user time,water and energy. When using a dishwasher instead of doing dishes by hand a lot of energy issaved.The importance of lowering the energy consumption does not only come from the consumerwinnings but also from an environmental point of view. Scientists are certain that the globalwarming comes from the emission of green house gasses that is created by human consumptionof oil, gas and coal.Dishwashers today are a lot more energy efficient than older dishwashers, but there are stillmargins to lower the energy consumption. The aim with this project is to investigate thedishwasher and it?s washing cycle, noting different phases and components that contribute towaste of energy.

The purpose of this report is to investigate the possibilities with drain water heat recovery (DWHR) in residential buildings. Information and relevant theory has been collected and summarized in this report. Calculations have been done for given scenarios to evaluate profits. DWHR heat exchangers use simple technology and have long life-time. The heat exchanger is connected to outgoing drainage pipe and incoming cold-water supply so countercurrent flow is accomplished.

Sweden?s energy consumption is divided into three major sectors. One of them is the industry sector. One third of Sweden?s energy consumption is converted in the industries.

The objective of this study is to examine the sustainability of recovering industrial wasteheat from several heat sources in a foundry constructed in a plant belonging to ITT Waterand Wastewater in Emmaboda, Sweden. A triple bottom line perspective will be appliedto achieve this objective. The triple bottom line approach takes into account ecologicaland social performance in addition to financial performance. The technology forrecovering the waste heat is a Borehole Thermal Energy Storage (BTES) which is aconstruction consisting of 140 vertical boreholes, 150 meters deep with an internal spaceof four meters.The calculated amount of energy for storage is approximately 3800 MWh annually. Ofthis amount 2500 MWh are expected to be utilized, while storage losses accounts for theremaining part.

The energy in laundry rooms, in form heated air, can be utilized with a heat exchanger. A concept and an early prototype of the heat exchanger have already been developed to show that the theory works. This report describes the continued development and construction of the product.A field study was made in order to investigate the environmental usage and establish the product design. The most common washing machine was used as a calculation model, and calculations were also made to estimate the amount of energy in the air. A previous analysis of the existing prototype is also presented in this report, to show the products potential capacity.

When a combined heat and power plant produces heat and power it often faces a deficit of heat load during the summer or other periods of time. This heat is often unnecessarily cooled away or the power production has to be reduced or shut off. If it is possible to store heat from periods with low heat demand to periods with high heat demand one can get many benefits. Among these benefits are: increased power production, decreased operation with partial load, uniformly distributed load.To be able to store heat in situations like this long-term thermal heat storages are needed. In this thesis five different types of stores are presented: rock cavern storage, tank storage, pit water storage, borehole storage and aquifer storage.

Thermia Värme AB is one of the market leading manufactures of heat pumps. In order tomaintain this position, the company wants to improve the vibration characteristics of theirproducts. The aim of this thesis is to develop product design changes that lead to a reductionof vibrations in the heat pump Thermia Diplomat 8.The main cause for vibrations in the system is flow pulsation and mechanical forces inducedby the scroll compressor. Vibration is transmitted through the compressor piping and receivedby the heat exchangers, from where it is further transmitted to the connection points for theradiator and heat source circuits.A number of design changes in order to improve the vibration characteristics have beenevaluated through calculations and practical experiments. The changes have included thecompressor and heat exchanger mountings, the compressor suction and discharge line pipingand also pulsation dampening.The results of the experiments show that the vibration levels in the connections for the heatingand brine circuits can be decreased strikingly through changes in suction and discharge linepiping.

Stockholms vattenskärning AB in Kungsängen has through the acquisition of a company begun to design and produce aircraft heaters whose origin is early 1970s which follows a high inefficiency in terms of energy consumption and size.The aircraft heater, which is sold worldwide, serves its purpose for customer satisfaction and has done so ever since it was developed in the 70s.Stockholms vattenskärning AB is now investigating the possibility in making the aircraft heaters more efficient, both in terms of energy consumption but also on a more efficient design with the belief that it would lead them to an edge in the market. The aircraft heater consists of several main components whose function altogether is to keep passenger aircrafts warm while they are on the ground.This project has been limited to the further development of the heat exchanger package which accounts for the conversion of the hot medium to the fresh air being carried in to the aircraft cabin. Work has been divided into different phases in order to create a better understanding of the project range and to make it easier to divide the various elements in the time available, 10 weeks. These phases are literature review, situation analysis, concept generation, CAD, concept comparison and writing reports.After the initial literature review was made, a fundamental theory was written which is essential in understanding the remaining parts of the project.With the theoretical part as support, measurements and calculations were made on the current heat exchange package in a situation analysis to ensure its operation and efficiency.In the concept generation phase, the collected facts from the literature review was used as the basis for creating a matrix. The purpose of the matrix was to indicate the two most suitable types of heat exchangers to develop four new concepts out of.In the CAD phase the four concepts was drawn up and then described with text and images.The last phase is the concept comparison where a concept selection matrix is used to function as a decision basis for further production at Stockholms vattenskärning AB. The four concepts have been developed based on the current heat exchanger and is gradually changed into a design of a cross-flow heat exchanger constructed out of stainless sections. The purpose of this is to have gradual upgrading of the heat exchanger as an option, in order not to saturate the market..